251P - Body mass index as a predictive factor for efficacy of taxane-based chemotherapy in early breast cancer patients

Background

Adjuvant anthracyclines and taxanes reduce risk of recurrence and death in Early Breast Cancer (EBC) patients (pts) but the toxicity profile is a major concern. Several studies have shown conflicting results correlating Body Mass Index (BMI) and outcomes in these pts. There are limited data on the efficacy of adjuvant taxanes among BMI categories. The prognostic effect of BMI on disease recurrence between adjuvant Paclitaxel (P)-based Chemotherapy (CT) vs. Docetaxel (D)-based CT has not ever been reported.

Methods

Pt-level pooled analysis of 13,486 EBC pts treated with adjuvant anthracyclines +/- taxanes from 7 GEICAM & TRIO adjuvant randomized controlled trials (RCTs) carried out from 1996 to 2008. Pts were classified in 4 BMI (kg/m2) categories: normal (< 25.0), overweight (25.0 to 29.9), obese (30.0 to 34.9), and severely obese (≥ 35.0), to evaluate BMI as a predictive factor for efficacy and toxicity of adjuvant taxane-based CT. Hazard Ratios (HR) were calculated using a Cox proportional hazard model stratifying by RCT.

Results

Pts distribution based on BMI was: 44% normal, 33% overweight, 16% obese, and 8% severely obese. 79% were treated with taxane-based CT (83% with D and 17% with P). 10y iDFS was 71%, 70%, 68% and 64% in normal, overweight, obese, and severely obese pts who received CT, respectively, being statistically significant in obese (HR 1.15; 95% CI 1.05-1.26; p=0.002) and severely obese (HR 1.29; 95% CI 1.15-1.45; p<0.001). 10y iDFS by type of CT are describe in the table. Relevant toxicity was 5%, 5.5%, 5.9% and 9.3% in normal, overweight, obese, and severely obese pts who received D. Table: 251P

Conclusions

Prognosis is worse in heavier vs. leaner EBC pts receiving adjuvant taxane-based CT. Leaner pts receiving D (compared to non-D) achieved a better outcome, while pts who benefited most from P were the obese subgroup (compared to non-P).

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

GEICAM Spanish Breast Cancer Research Group.

Funding

Has not received any funding.

Disclosure

J.A. García-Sáenz: Financial Interests, Personal, Advisory Role: Seagen, Astrazenecea, Daiichi Sankyo, Novartis, Gilead and Menarini; Financial Interests, Personal, Speaker, Consultant, Advisor: Celgene, Eli Lilly, EISAI, MSD, Exact Sciences, Tecnofarma, Nolver; Financial Interests, Institutional, Funding: AstraZeneca; Financial Interests, Personal, Other, Travel support: Novartis, AstraZeneca and Pfizer. M.A. Pollán: Financial Interests, Personal, Advisory Board, Participation in the elaboration of a divulgative summary on predictive medicine: Ascendo; Financial Interests, Personal, Invited Speaker, Speaker in a scientific event: Roche. M. Ruiz Borrego: Financial Interests, Personal, Speaker, Consultant, Advisor: Roche, AstraZeneca, Daiichi Sankyo, Pierre FABRE, Pfizer, Novartis, Gilead; Financial Interests, Personal, Advisory Role: Daiichi Sankyo, Gilead and Pierre Fabre. M. Martin Jimenez: Financial Interests, Personal, Advisory Board: AstraZeneca, Lilly, Roche/Genentech, Daiichi Sankyo, Menarini-Stemline; Financial Interests, Personal, Invited Speaker: Pfizer, AstraZeneca, Lilly, Novartis, Roche/Genentech; Financial Interests, Institutional, Research Grant: Novartis, Roche, Puma; Non-Financial Interests, Member of Board of Directors: TRIO; Non-Financial Interests, Leadership Role: GEICAM; Non-Financial Interests, Member: ASCO; Non-Financial Interests, Advisory Board: SEOM. A.L. Guerrero Zotano: Financial Interests, Personal, Advisory Role: Pfizer, AstraZeneca, Pierre Fabre, Novartis, Exact Science, Stemline; Financial Interests, Institutional, Funding: Pfizer; Financial Interests, Personal, Speaker, Consultant, Advisor: Roche, MSD, Novartis, Pfizer, AstraZeneca, Daiichi Sankyo, Pierre Fabre, Exact Science. A. Rodríguez-Lescure: Financial Interests, Personal, Speaker, Consultant, Advisor: Pfizer, Novartis, AstraZeneca, Daiichi Sankyo and Seagen ; Financial Interests, Personal, Advisory Role: Pfizer, Novartis, Roche, AstraZeneca, Daiichi Sankyo, Pierre Fabre and Seagen. All other authors have declared no conflicts of interest.